The present invention relates to an information transmitting/receiving system for transmitting and receiving content information such as audio/video information over a network, to an information transmitting apparatus and an information receiving apparatus which make up the information transmitting/receiving system, and to an information transmitting/receiving method corresponding to the information transmitting/receiving system.
Applicant has proposed an information transmitting/receiving system designed to connect a base station apparatus with a monitor apparatus wirelessly, the system functioning typically as AV (audio video) equipment (see Japanese Patent Laid-open No. Hei 8-79847).
The base station apparatus of this information transmitting/receiving system may illustratively include a TV broadcast tuner capable of selecting TV broadcast signals and demodulating or decoding the received signal into audio/video signals. When equipped with audio/video input terminals, the base station apparatus may also input externally supplied video/audio sources through the terminals. The video/audio information thus acquired may be converted by the base station apparatus into compression-encoded audio/video data which in turn may be output wirelessly.
The monitor apparatus is illustratively a device small enough to be carried around in the room. In operation, the monitor apparatus receives the video/audio data transmitted wirelessly from the base station apparatus and decodes the received data into images and sounds to be output.
With the above information transmitting/receiving system in use, the user may illustratively carry around the monitor apparatus indoors and set it up where desired. Within a communicable range of the base station apparatus, the monitor apparatus may be located wherever desired to let the user view and enjoy TV broadcasts and content information such as video/audio information that has been input to the base station apparatus.
It is the monitor apparatus that operates the controls of the base station apparatus, such as those for tuning in to TV broadcasts and selecting audio/video sources. The information reflecting the operations is transmitted to the base station apparatus. On receiving the operation information, the base station apparatus carries out the corresponding controls causing illustratively the tuner to switch channels and changing input audio/video sources.
The information transmitting/receiving system outlined above may be considered a system having two kinds of equipment installed separately: equipment typically for inputting and acquiring audio/video sources (i.e., base station apparatus), and the monitor apparatus for outputting the audio/video input. When audio/video data is transmitted wirelessly from the base station to the monitor apparatus, the user is given a certain degree of freedom in selecting the location to view and enjoy the content information within a relatively limited range such as inside the house.
Where the above information transmitting/receiving system is established, the base station apparatus and the monitor apparatus may both be provided with the ability to connect with a network such as the Internet or a LAN (local area network). The connection allows the base station apparatus and monitor apparatus to exchange audio/video data and other content information over the Internet.
Given the capability to communicate over the Internet, the monitor apparatus is no longer subject to constraints on where to set up the connection as long as access to the Internet is ensured. In that case, the information transmitting/receiving system may be used in the following application:
The base station apparatus is established in a place remote from where the user utilizes the monitor apparatus. For example, the base station apparatus is installed in a service area far away from the service area of TV broadcasts covering the region where the monitor apparatus is to be used. The base station apparatus and monitor apparatus are then arranged to exchange not only audio/video data but also commands.
In that setup, the user is able to control the base station apparatus via the Internet so that the audio/video data of a selected TV broadcast received and demodulated by the base station apparatus may be sent to the monitor apparatus for audio/video output. In other words, a TV broadcast from a different area which is ordinarily not receivable in the area where the user is operating the monitor apparatus can be viewed through the Internet connection by the user remaining in that area.
Described below with reference to FIG. 8 is a procedure performed by the base station apparatus and the monitor apparatus to exchange audio/video data therebetween over the Internet. Steps constituting the procedure are indicated in FIG. 8 together with encircled numerals representative of the sequence in which they are to be carried out.
The information transmitting/receiving system made up of a base station apparatus 1 and a monitor apparatus 2 shown in FIG. 8 maintains a one-to-one correspondence between the two components. That is, one base station apparatus is made to correspond with one monitor apparatus within the system. To establish the one-to-one correspondence over the Internet requires first registering the user's monitor apparatus 2 with the base station apparatus 1 in step 1. This step, when carried out, causes the base station apparatus 1 to handle the registered monitor apparatus 2 alone as a legitimate apparatus to which to send audio/video data.
After the registration in step 1, the user may illustratively operate the monitor apparatus 2 to view a TV broadcast. In that case, the monitoring apparatus 2 in step 2 sends a transmission request command to the base station apparatus 1 over the Internet, the command being arranged to request the base station to transmit the audio/video data making up the selected TV broadcast to the monitor apparatus 2.
The base station apparatus 1 inputs TV broadcast waves received by an antenna, not shown, and causes an internal tuner to demodulate the received signals to acquire audio/video information from the outside. Upon receipt of the transmission request command in step 3, the base station apparatus 1 performs an authentication process, i.e., the apparatus 1 determines whether or not the monitor apparatus 2 having sent the command is an apparatus duly authorized to receive audio/video data. The authentication process involves determining whether or not the monitor apparatus 2 having sent the command is a registered monitor apparatus. More specifically, the ID of the monitor apparatus having transmitted the command is checked against the IDs of the registered monitor apparatuses for a match, the IDs constituting registration information.
When the monitor apparatus is found to be a legitimate monitor apparatus authorized to receive audio/video data as a result of the authentication process in step 3, the base station apparatus 1 in step 4 outputs the requested audio/video data on a streaming basis. Illustratively, the command requesting the transmission of audio/video data may designate a TV broadcast channel. In such a case, the base station apparatus 1 receives and demodulates the selected TV channel signal so as to acquire audio/video signals, encodes the acquired signals into compressed audio/video data, and transmits the compressed audio/video data in streaming fashion to the monitor apparatus 2 over the Internet.
In step 5, the monitor apparatus 2 receives the compressed audio/video data transmitted in a streaming manner in step 4. The audio/video data thus received is decoded into images and sounds which are output on the monitor apparatus 5.
With audio/video data transmitted and received in the above-described manner, the base station apparatus 1 may be established in an area remote from where the monitor apparatus 2 is used. This setup allows the user of the monitor apparatus 2 to watch TV broadcasts that are ordinarily not receivable from the user's current location. Naturally, the audio/video sources formed by the audio/video signals output by AV equipment connected to the base station apparatus 1 can also be received and output by the monitor apparatus 2 for the user to enjoy.
The above-described information transmitting/receiving system is predicated on the condition that the base station apparatus 1 and the monitor apparatus 2 communicate with each other on a one-to-one basis. It follows that, while the monitor apparatus 2 can get TV broadcasts not ordinarily receivable in the area where the apparatus 1 is being used, such out-of-area broadcasts rendered receivable are limited to those from the area where the corresponding base station apparatus 1 is set up. External audio/video sources that can be enjoyed are also limited to those from the AV equipment connected to the corresponding base station apparatus 1.
That is, even if the user wants to enjoy more audio/video contents than before, e.g., more TV broadcasts from more service areas or more audio/video sources from more pieces of AV equipment, such wishes are difficult to meet as long as the user's connection is subject to the requirement of one-on-one correspondence: the base station apparatus 1 and the monitor apparatus 2 must communicate with each other on a one-to-one basis.